So we built a utility that creates a DNSBL file from users spam reports, it does this based on several factors. For high traffic services it can also be set to require more than one report in order to add it to the black list. Just curious if anyone else is interested in this? It's 100% functional and working well but we were looking at adding more features like URLBL based on body content of emails and a few other things. If anyone else is interested in collaborating on this please let me know.